What it is and what it does
The Siemens 3VA2110-5MN36-0AC0 is a SENTRON molded case circuit breaker (MCCB) sized for motor protection duty. It's a 3-pole unit rated at 100 A continuous current (Iu) and carries an ETU350M electronic overcurrent release — that's the brain that decides when to trip based on motor-start inrush and running overloads without nuisance opening. The breaker also includes phase failure detection, so if you lose a leg on a three-phase motor feed, it drops the load before single-phasing cooks the winding.
Breaking capacity — the so-what
Breaking capacity is where this breaker earns its keep on high-fault panels. At 240 V it interrupts 187 kA; at 415 V and 440 V it still holds 121 kA. That's enough for most industrial service-entrance or large-motor branch circuits where the available fault current is high. At 690 V it drops to 17 kA, which is still respectable for a 100 A frame in that voltage class. The rated insulation voltage is 800 V, so the breaker is built for 690 V systems with margin.
Thermal derating and panel fit
The 100 A rating holds all the way to 50 °C ambient — no derating needed in a typical ventilated enclosure. Above that it steps down: 96 A at 55 °C, 94 A at 60 °C, 92 A at 65 °C, and 90 A at 70 °C. If your panel runs hot (near a motor drive or in a sun-baked cabinet), you lose about 10 % of capacity at the top end. The breaker dissipates up to 75 W at full load, so factor that into your enclosure thermal budget. Dimensions: 181 mm high, 105 mm wide, 86 mm deep — standard SENTRON 3VA frame footprint, so it drops into existing panel cutouts and busbar layouts without rework.